Lauriol plaza, in Washington, D.C., is one of those restaurants where it's hard to hear your voice over the din by 6 p.m. Salsa music blares. Waiters yell out to one another as they hoist platters of sizzling fajitas over their heads. The bar is packed with revelers armed with table beepers and margaritas the size of small fishbowls.

A few years back, an elegant female patron, infuriated about the long wait for a table, demanded to speak with the owner. Luis Reyes approached and introduced himself.

"I asked to speak with the owner," the woman said.

"How can I help you?" he asked.

The woman gave the moon-faced, mocha-skinned proprietor a once-over and shook her head. "You can't be the owner," she told him.

Lauriol Plaza workers have taken such relish in recounting the anecdote that it's become folklore in D.C.'s Salvadoran community. It's not hard to see why: It demonstrates how little separates them from their boss. Reyes, the co-owner of Lauriol Plaza and a sister restaurant called Cactus Cantina, may be a millionaire whose establishments have served local celebrities such as Al Gore, Bill Clinton, and Michelle Obama. But he started out just like his workers, a poor immigrant washing dishes.

It's a poignant rags-to-riches tale, but it doesn't end there. Not only has Reyes built a successful business in his adopted country; he has become a political kingmaker in his native one. He and a group of Salvadoran expat entrepreneurs played a key role in dislodging the right-wing National Republican Alliance, or ARENA, from power in 2009, ushering in the first progressive government in the country's history. And Reyes, who fled El Salvador's crippling poverty at 16, is now considered potential presidential material himself.

Reyes had long sought to upend his nation's political culture. In the early 1980s, he nearly returned to join the guerrilla army waging war against an often-brutal military government. Back then, it seemed that change would come only through force. Instead, he stayed behind and became a successful restaurateur. He couldn't have known it then, but taking that route positioned him to play the influential role he craved.

"It gave me a chance to help in a different way," Reyes tells me with a sly smile. "It turns out I was worth more alive."

Reyes left El Salvador in 1977, with $150 sewn into his jeans pocket. The $450 he had paid a coyote to smuggle him into the States proved a bad investment: The man abandoned Reyes and 54 others in the desert outside Piedras Negras, Mexico, near the Texas border. After going without food for five days, Reyes and four others decided to go forward on their own.

He arrived in Washington on New Year's Day, 1978. He moved into a studio apartment, shared with nine roommates, and found work--washing dishes at a steak house and cleaning offices. The bulk of his earnings went straight back home, something else he shares with his current employees. In 2011, these remisas totaled $3.6 billion, or 16 percent of El Salvador's GDP, and they are crucial for countless Salvadorans.

Today, he lives in an elegant brick home in D.C.'s tony Forest Hills neighborhood. Its circular driveway sports a Land Rover and an Audi SUV. Inside, a basement bar features a photograph of Reyes and Salvadoran President Mauricio Funes, their arms clasped around each other's shoulders. In fact, the president once lounged on the plush sectional leather sofa in the room, along with the future foreign minister and the president of the senate.

The house Reyes grew up in, by contrast, had no indoor plumbing or running water. He didn't own a pair of shoes until he got some cheap loafers at age 7. For weeks, he walked peering over his shoulder to catch sight of the footprints the soles made on dirt roads.

Most Latin American countries have monstrous class systems, but even in that context, El Salvador stood out. A small elite owned 60 percent of the country's arable land and pretty much all of its industry. Elections that didn't go the way the elite wanted were stolen.

By 1980, a left-wing army, the Farabundo Martí National Liberation Front, or FMLN, had thousands of fighters, and it looked as if it might take over the country. The Reagan administration announced that wouldn't happen on its watch, and over the next 12 years the U.S. provided the country with more than $4 billion in aid, much of it going to the Salvadoran military and its death-squad allies.

Reyes had decamped to the States before the official outbreak of the war. He built a new life in Washington, becoming a husband and a father, working his way up to assistant chef at the steak house. But he understood why people were taking up arms, and on Sundays, his sole day off, he often attended raucous meetings in support of the FMLN.

At one of those events, in January 1981, FMLN supporters held a recruitment rally in Dupont Circle. "The fight goes on," one of the recruiters shouted in Spanish through a megaphone, "and we need your help to win it." When the man asked for volunteers to return to El Salvador, Reyes raised his hand.

He didn't end up going. For one thing, he was undocumented, so leaving almost certainly meant exile from his new home. He also suspected it could amount to a suicide mission. "A lot of the men who raised their hands never came back," he says.

Instead, Reyes worked. His employer sponsored him for residency, and by 1983, he had saved $20,000, which he used to co-found Lauriol Plaza. He became a U.S. citizen in 1986, and a few years later, he and his Cuban-born partner, Raul Sanchez, launched Cactus Cantina. His approach to business won't win any award for novelty: Offer a quality product, with good service, at a reasonable price in an agreeable setting. Add to that hard work and sacrifice: For 16 years, he and his partner postponed their paydays and reinvested their profits.

By the mid-'90s, Lauriol Plaza was a D.C. institution. It became a two-hour-wait kind of place when Reyes and Sanchez built an airy, four-story building for their flagship restaurant. On weekend nights, the restaurant serves an average of 2,100 meals.

On Friday nights at Lauriol Plaza's bar, Reyes would often gather with other Salvadoran expats--men like Leonel Flores, who grew up shining shoes on the streets of San Miguel and became a medical researcher at the University of Maryland. It drove them to distraction that the ARENA party had managed to win four successive elections since the end of the civil war in 1992. They mused about all that could be done if the government made no-brainer changes, like providing universal education. The rambling conversations were bittersweet: Anything was possible in their ideal world, but for men accustomed to getting things done, it felt as though they were spinning their wheels.

In 2005, the Lauriol Plaza crew saw a tantalizing opening to finally take on ARENA. Mauricio Funes, a CNN en Español correspondent, stopped by the restaurant one night and told the group that he planned to run as the FMLN candidate in the 2009 election. Reyes and his companions immediately grasped the potential of a Funes candidacy. FMLN candidates still tended to be hoary ex-guerrilla fighters who espoused taking over private enterprises, which lent credence to ARENA's allegations that they were communist throwbacks. Funes, by contrast, was both telegenic and not prone to rants about U.S. imperialism.

To be competitive, Funes needed two things: cash and support from his country's business community. In fact, several Salvadoran business leaders who had soured on ARENA had started a group called Amigos de Mauricio, or Friends of Mauricio. On a long August night in 2007, Reyes and his companions congregated around the bar at Lauriol Plaza and committed to launching a parallel organization in the U.S.

When the men clinked glasses over the new organization, Reyes felt a rush that he likens to the feeling he had when he first opened the doors of Lauriol Plaza. Rather than complaining about his homeland's dysfunctional political culture, he was finally doing something to shake it up.

The days when U.S. aid amounted to more than $250 million a year are long over, but El Salvador remains heavily dependent on the U.S. because of the dollars Salvadorans send back home. ARENA had long exploited that connection, claiming that an FMLN win would scare off business and alienate the U.S. government. In 2004, for example, the party ran an ad featuring an abuelita sobbing over a letter from her grandson: The monthly checks, he had written, were coming to a halt and he was facing deportation, because the FMLN was now in power.

One way to counter that message was to get actual members of the Salvadoran diaspora to encourage voters to support Funes. One of Reyes's comrades--Carlos Zelaya, a Baltimore real estate developer--came up with the idea of distributing 20,000 phone cards at Funes fundraising events across the United States, each with enough for a five-minute phone call home. "We told people, 'Take three, and get in touch with your grandmother, your brother, and your former neighbor,' " Zelaya says.

Reyes grows anxious when he is away from Lauriol Plaza for more than a few days. ("In order to make a restaurant work, you really have to be in it," he says.) But in the run-up to the election, he took two 10-day trips to El Salvador. He had hosted a highly successful fundraiser in Washington, and at Funes's behest, he agreed to organize one in San Salvador. He spent weeks making in-person appeals and phone calls, rounding up 40 U.S.-based Salvadoran businessmen to make the trip home and pay $1,000 to attend. They posed before a bank of TV cameras before filing into the stately Hacienda de los Miranda restaurant and gave a press conference afterward. The event sent an important message: Funes was a man business could work with.

When the ballots were tallied on March 15, 2009, Funes had edged out his rival, 51 percent to 49 percent. Since then, many of the ideas Reyes and the Lauriol Plaza clan discussed have become a reality. Basic education is now free. Poor students are provided with uniforms and--in a move with particular resonance for Reyes--shoes. The president muscled through a modest tax-reform program. El Salvador has been riven by gang violence for two decades, but in April the country had its first murder-free day in memory.

To be sure, it's only a start. But none of it could have happened without Reyes and his fellow businessmen, says Michael Allison, an associate professor of political science at the University of Scranton. "The business support was necessary," Allison says. "It brought a credibility and moderation to the party that it badly needed."

Not long ago, over freshly squeezed orange juice at Lauriol Plaza, I asked Reyes why he had worked so hard to get Funes elected. He talked about how brutal his early life had been. And then he brought up the choice he had made decades back not to join the guerrilla effort. That decision seemed to gnaw at him. "I'd wanted to participate in a direct way," he said, as he looked down at the snowy tablecloth. "Those men were fighting for a just cause." His role in the 2009 election, and the bloodless coup it brought, seems in part to have been a way to atone.

Reyes spread out on the table pictures of him with Funes and the minister of justice, as well as receipts of airline tickets he bought for the then-presidential candidate. "It's not just that they meet with me," he says. "They listen to me."

Like many ambitious people, Reyes seems perpetually driven to build on what he has accomplished. Most days, he works at Lauriol Plaza until midnight or later. He admits that the grueling schedule has strained his marriage, but in the next breath, he talks about opening a third locale.

Will Reyes's business be enough to satisfy his ambitions? Salvador Sanabria, a Salvadoran expatriate who runs El Rescate, an influential nonprofit in Los Angeles, doesn't think so. The ascension of an expat to the presidency of El Salvador is inevitable, Sanabria believes. And no one, he says, has a better narrative to peddle to voters than Reyes. "He'll be president one day," Sanabria says.

When I bring this up with Reyes, he laughs. His role, he insists, is to propose ideas and help fund progressive candidates. And then he flashes one of his impish smiles. "That said," he says, "I'm not ruling anything out."